Most played cards in Madness:

1 Decks
Once Upon a Time
4 copies - 4 average
Vengevine
4 copies - 4 average
Faithless Looting
4 copies - 4 average
Burning Inquiry
4 copies - 4 average
Faerie Macabre
4 copies - 4 average
Putrid Imp
4 copies - 4 average
Lion's Eye Diamond
4 copies - 4 average
Hollow One
4 copies - 4 average
Basking Rootwalla
4 copies - 4 average
Anje's Ravager
4 copies - 4 average
Blazing Rootwalla
4 copies - 4 average
Ancient Grudge
3 copies - 3 average
Firestorm
3 copies - 3 average
Bone Shards
3 copies - 3 average
Bloodstained Mire
3 copies - 3 average
Anger
2 copies - 2 average
Ox of Agonas
2 copies - 2 average
Gamble
2 copies - 2 average
Wooded Foothills
2 copies - 2 average
Badlands
2 copies - 2 average